AVCS Tuning

[HolyCrapItsFast]

Here are my final results... I'm quite pleased with this torque curve... Again keep in mind that this is on 92 octane fuel. Torque comes on nice and early and maintains a nice level right to red line... usable boost @ 3800 and full boost @ 4400 with an MBC. I have convinced him to reconnect his EBCS because we can vastly improve that with the ECU controlling boost, but that this exercise was done with an MBC this demonstrate the effect that AVCS can have on spool without the factory EBC mucking up the results by trying to compensate.

 

[Td_d]

What advance are you running in the mid rpms, heavy loads, Fuji?

 

[Td_d]

And what I mean is I used the values for your map and just cleaned up AFRs and timing for safety and lack of knock. It was a good experiment, but because our setups are so radically different, your map will not work properly for my car. Wanted to atleast be able to show what does not work.

By the way, I'm going to start using this thread more for a repository of data about AVCS and other related VVT systems.

http://www.streetracersonline.com/articles/camshafts/3.php

Ah, ok - yeah, I've battled so much with resonance, that my fueling, timing and AVCS was very specific to dealing with those issues - wouldn't think it would work on another setup (especially FMIC and much bigger turbo).

I must try Holy's AVCS approach - very curious to see the results.

 

[Td_d]

I'll pm you a shot first, k?

 

[Td_d]

Works spectacularly, that's all I can say - the ramp up is absolutely brutal.

 

[HolyCrapItsFast]

Thanks guys... I don't need to see that. :tup:

 

[HolyCrapItsFast]

I'm just kidding!

 

[Td_d]

Thanks guys... I don't need to see that. :tup:

You got mail

I'm just wary of publishing the actual map, given that it is a commercial tuner, and it's not my IP. I'd rather discuss the approach here.

And by the way - he's also a big proponent of road tuning. His take is that on the AVCS side, due to the way loads differ between dyno and actual driving, there's no way this map could have been properly done on a dyno.

 

[HolyCrapItsFast]

You got mail

I'm just wary of publishing the actual map, given that it is a commercial tuner, and it's not my IP. I'd rather discuss the approach here.

And by the way - he's also a big proponent of road tuning. His take is that on the AVCS side, due to the way loads differ between dyno and actual driving, there's no way this map could have been properly done on a dyno.

I totally agree with this

 

[Bigbadbenny]

I've noticed something very weird on my intake right versus intake left AVCS - and I'm not sure whether it's a quirk after a new flash, or a mechanical issue (I need to further examine later, post flash logs to see if there's a trend). At spool up - so I'm assuming lower oil pressure - the right intake AVCS lags the left intake significantly sometimes - 10-12* - then catches up - and overshoots signficantly. I saw it go up to 53*on one run (left intake was close to target at 31*). WTF? The GR's no longer have banjo bolt filters, right? Solenoids? What should I look for - or am I being paranoid?

Did you get this issue sorted and if so what was causing the issue?

 

[Bluedemon_II]

Ok, I'm going to apply most of the stuff that I have read here to my genesis. Lets see if the general knowledge applies over platforms. I have intake and exhaust vvt but never touch them for the sheer fact that I was unsure on how to go at them. Freakishly small turbo wont help out but lets see how it goes. I did play with intake avcs on my 04 sti and manage to increase airflow given that I went leaner on a/f and maf voltage went higher, this was advancing timing after 3.5krpm.

 

[Bluedemon_II]

My butt dyno says that I gained a few ponnys after 5000 rpm. I need to hit the dyno but sadly I have no clutch.

 

[HolyCrapItsFast]

Here is a recent tune I was working on and this example shows almost no difference between 0 and 22 degrees of valve advance on the intake cam. It could be due to the fact that it is at altitude but there is just not any significant difference. The user did indicate that there was a significant difference in drivability though and 10 and 15 felt the best according to the butt dyno. The biggest difference was with torque in the lower RPMs

All four pulls were done under the exact same conditions on the same stretch of road each time and back to back.

 

[Grinder34]

im having trouble getting the image to work